Account for axial vector mesons in the $\eta \to {\pi }^{+}{\pi }^{-}\gamma$ and ${\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}\gamma$ decays

A. A. Osipov, A. A. Pivovarov, M. K. Volkov +1

The rates and spectra of the anomalous $\eta \to {\pi }^{+}{\pi }^{-}\gamma$ and ${\eta }^{\prime }\to {\pi }^{+}{\pi }^{-}\gamma$ decays are calculated. The approach is based on the effective meson Lagrangian obtained in the Nambu-Jona-L…